Here's how to tie it with a 5 3/8 side release fastex buckle.
Apologies for the sub-par pictures. I had trouble holding the camera steady and the knots tightly.
Step 1: Materials
These can be two different colours if you like.
2) A side release buckle. 5 free samples are available from the ITW Nexus website or you may purchase them from Supply Captain.
3) A lighter or thread matching the colour of your cordage.
1) A knife or a pair of scissors